Our church, along with many churches in the Chicago area, is doing a sermon series entitled “Explore God.” The series is based around seven questions relevant to the Christian faith, and to people exploring the Christian faith.

  1. Does Life Have a Purpose?
  2. Is There a God?
  3. Why Does God Allow Pain and Suffering?
  4. Is Christianity Too Narrow?
  5. Is Jesus Really God?
  6. Is the Bible Reliable?
  7. Can I Know God Personally?

My plan is to write my own answers to these questions. I welcome engagement from people of all backgrounds in the comments or by email. I look forward to revisions and corrections that arise from that dialogue.


tl;dr: Yes

Once more I feel the need to tweak the question. God either exists or does not exist. Whatever you and I happen to think about the matter will not make a difference to God’s existence. The question we are confronted with, however, is whether we can know that God exists. I myself would phrase the question in one of two ways: “Can one responsibly believe that God exists?” or “Is one (morally/epistemically) obligated to believe that God exists?”

First I would like to establish some preliminaries about belief and doubt.

Some knowledge comes to us in the form of mathematical proofs. These are very trustworthy and very useful. It is remarkable that one can begin with a small number of commonsense assumptions, and then show with logic that the Pythagorean Theorem has to be true. These are very important truths, and we are very certain of their truth.

Sometimes, however, we inappropriately demand that other sorts of truths be verified with the kind of certainty that we have for mathematical truths. Almost none of the knowledge we value comes with this level of certainty. Do your parents love you? Is your spouse faithful? Is your contribution at work valued? Are you making a difference in the world? Has my food been poisoned? It’s simply not an option to have mathematical certainty about those kinds of things, but we manage to make intelligent decisions nonetheless.

Skepticism is a powerful acid: it can dissolve just about any belief. Some people believe that the moon landings were faked. Some people believe that the earth is flat. I raise these examples, not to endorse simpleminded faith in anything, but to make the observation that skepticism can become unhealthy. There comes a point—not always an easily recognizable point—when skepticism has been replaced with a simple desire not to believe in something. I have never spoken with people who doubt that the moon landings took place, but I imagine they would pride themselves on being strictly logical, and regard me as a gullible dupe.

The philosopher René Descartes was thinking about doubt one day, started doubting a lot of things, and finally realized that he couldn’t be certain about anything in his life. After all, perhaps an evil angel was deceiving his senses, and his whole life was nothing but a demon-created fantasy. (His famous Cogito ergo sum—I think therefore I am—is the only thing he found he was not able to doubt.) Times change. People in my generation would ask, “Am I stuck in The Matrix?” Philosophers nowadays ask about the brain-in-a-jar scenario: am I a brain in some scientists’ jar, being fed stimuli that make me believe this reality that I am confronted with?

We’re never going to be 100%, no-possible-doubts certain—about anything. This is the reason that the question really ought not to be whether God exists, but whether it is responsible or obligatory to believe in God. I can’t be sure that I’m not a brain-in-a-jar, but it would be irresponsible for me to live as if that were the case. I shouldn’t drive a car off a cliff just because I’m not sure that the cliff is real.

Another important preliminary: the question of God’s existence is not simply a matter of curiosity. Until recently, physicists wondered if there were such things as Higgs bosons. Experiments performed with the Large Hadron Collider have apparently shown that the answer is yes, they do exist. Frankly, I don’t know enough about the physics to understand why that is an important or an interesting question. It’s certainly not had an influence on my life. It’s not as if I were going to disbelieve in mass if they hadn’t found that particle. Nevertheless, I can appreciate that the science is important, if only to fill out a blank spot in our knowledge of the universe.

But that’s not the same kind of question as whether or not God exists. The question of God’s existence is much more like the question of whether industrial activity is contributing substantially to climate change. That is a question with some urgency to it. It is a question the answer to which we cannot be 100% certain. But it is nevertheless a question that we cannot afford to ignore. Inaction is itself a decision. If we wait for 100% certainty we might all die.

The question of God’s existence is like a surgeon looking at a length of human gut and wondering how much to cut: too much and the patient is harmed; too little and you don’t get all the cancer. A surgeon has to make a responsible choice; she can’t simply say, “Well, it’s impossible to know with absolute certainty how much I ought to cut out, so I won’t do anything.”

So, those are the stakes. That is the way I approach the question. This is not an intellectual exercise. We are faced with a decision. We are looking for heuristic evidence—evidence that points us in a certain direction, even if it does not absolutely require it—to make the best decision that we can make.

What I have below, therefore, is a collection of arguments that point us in a certain direction. None of these prove the existence of God, as we could prove the Pythagorean Theorem. Rather they all point in that direction.


Let’s begin with a thought experiment. Suppose I gave you a VR headset and showed you two different worlds. One is generated by a computer, with random initial conditions and some basic rules for how the world would develop. The other world is created by an artist. Would you trust yourself to determine which was which?

Cosmological fine tuning. The short version is, there are six dimensionless constants that, if they had different values, would mean that the universe would be a very different place, i.e., not as many kinds of atoms, no molecules, no existence as we know it. To all appearances, the probability of a universe that can sustain life as we know it at all are very, very small.

Now, if you stumbled across a well tuned guitar, you would know immediately that someone had been working on it; the parallel is, perhaps Someone has been working on the universe.

This is not definitive proof of the existence of God. One non-theistic option is a multiverse: that there is an infinite (or at least very large number) of universes, of which ours is the only viable one (or one of the few). Whimsically: things are so good, we must have won the lottery at some point in the past. The multiverse solves the mathematical problem, but there is no empirical evidence for it. It’s simply a way to account for the unlikelihood of what we have here before us.

With that qualification in place, I ask again: would you trust yourself to distinguish between a VR world that had been generated randomly, and one that had been designed intentionally?


Let’s now leave the physics, skip over most biological life, and come right to the human experience. In my previous post I wrote quite a bit about purpose and human existence, and now I will revisit those issues.

One application of the idea of purpose is the idea of truth. Truth is not simply a physical quantity. Here is a thought experiment to show that.

Imagine a student sitting in a room doing math problems correctly—filling out answers on an exam on which she’ll get 100%. Now imagine another student working in just the same way, and getting all of the answers wrong.

The question is: did the laws of physics apply in both rooms? If yes, then we see that truth is not something produced by physics. Truth is another sort of thing altogether, a personal judgment rather than a physical property of the system. (Computer programmers will understand this intuitively; even when a computer program is doing the wrong thing, it is following your instructions slavishly. Purpose comes from the creative act.)

Set aside truth and consider beauty. I do not believe that there are any unsolved problems in the physics of a sunset. But my reaction to a sunset is of a different nature entirely to my reaction to some equations about light defraction. White noise and a piano sonata can equally be coded in a physical medium: a WAV or MP3 file. The fact that one is music and the other is noise is a human judgment. (A computer can mimic the distinction if and only if a human gives it a heuristic to look for, such as a beat.) Milton’s language, physically conceived, has few surprises for me: it is nothing but ink on a page (or bits in an audiobook). But it has the power to move me as few other things can. The idea of beauty is something that comes from within a person.

I will touch on morality very briefly. Morality is not something that we attribute to animals. I understand that a lion, upon assuming leadership of the pride, kills all of the young lions. We have no moral judgment about that. Animal mating practices—again, not a moral concern. If you swap out the animals for humans performing those same actions, then we are looking at a moral nightmare. Just to make the point very simply: from a moral perspective, we do not behave like animals. If, in reality, we are nothing more than animals, then we are very deeply deceived about the moral nature of the universe.

We could multiply those examples, but let truth, beauty, and morality suffice for the present. If we are simply animals—i.e., complex molecular assemblies—then truth, beauty, and morality have no real existence. They are epiphenomena.

Lest I be misunderstood: I love reductionism. I wish I could understand the function of proteins in purely physical terms. I would love to understand language as arising from more general human cognitive abilities. But there are limits. A reductionist argument runs, “It’s not C, it’s just A + B.” Kepler’s Laws aren’t laws in themselves; they’re just epiphenomenal consequences of the law of gravitation. That’s the kind of reductionism I appreciate; it’s scientific explanation. But I will not therefore say, “There is no truth, it’s just utility” or “There is no beauty, the neurotransmitters just happen to do that, given those stimuli.” I cannot accept that kind of reductionism, because it damages the original insight.

Once more, I am not simply saying that I do not wish to believe that truth, beauty, and morality are illusions. This is not a “That’s not the sort of world I want to live in” sort of argument. I am saying that I do not believe that, as a matter of fact, those things are in fact illusions. Truth, beauty, and morality are bedrock components of humanity, simply at the level of description of what it is to be human.

Now, if that is accepted, then once again we have an orderly universe—truth, beauty, and morality—and we have to ask where that came from. Does it feel like the result of chaos, or does it feel like the result of an ordered system?


These two sources of order—order in the physical universe, order in the human experience of the universe—to my thinking, provide strong heuristic evidence for the existence of God.

There are other possibilities. The first—and the most likely, if I had to choose something non-theistic—is that I am after all just a collection of molecules spouting this stuff out. My lofty sentiments can indeed uttered by a machine:

10 PRINT "These two sources of order—order in the physical universe, order in the human experience of the universe—to my thinking, provide strong heuristic evidence for the existence of God."

If I am simply an animal, a complex collection of molecules, that what I am saying is equivalent to what the code above does. The evolutionary argument would be that the kind of collection of molecules that spouts out such stuff must be, on average, more likely to reproduce than the kind of collection of molecules that does not spout out such stuff. I can’t disprove that. (In fact, nobody can, but let’s set that aside for a moment.) But neither do I find it to be a convincing (much less compelling) scenario.

Another possibility is that we are living in a simulation. Apparently some people believe this nowadays. (They may or may not be aware that some time ago Augustine proposed that we all exist merely as thoughts in the mind of God.) This strikes me as a rather transparent attempt to simply avoid saying ‘God’—but there you have it. Perhaps we are living in a simulation.

But suppose all of these things are in place because they have been set in place by God. Even if one accepts that one ought to seek God, it doesn’t tell you which god to seek. The contemporary world provides several options, and the history of cultures provides more. If you accept the heuristic evidence presented here, it ends up not being so much a call to faith as a call to research. (Unfortunately, the next question you would probably want to ask— “Can I Know God Personally?”—is still several questions away.)

And, to bring this full circle, I would argue that there is a responsibility to do that research. We’re not placed here to kill time while we wait to be convinced of absolute truths. Whatever actions we take, or whatever actions we neglect, are decisions. They are commitments. We are liable for the results.